The present invention relates to water purification systems and methods, particularly to water purification systems and methods of using the same for producing water that is free of chemical, biological, and radiological (CBR) contaminants and suitable for human and/or animal consumption.
Water covers more than two-thirds of the earth""s surface. Nevertheless, there are many areas where water is scarce or where water, if available, is not potable and not suitable for human and/or animal consumption.
Various water treatment systems and methods have been developed for purifying unpotable water and rendering it suitable for human and/or animal consumption. An illustrative water purification system of such type is described in U.S. Pat. No. 5,741,416 issued Apr. 21, 1998 to Gerard F. Tempest, Jr. for xe2x80x9cWATER PURIFICATION SYSTEM HAVING PLURAL PAIRS OF FILTERS AND AN OZONE CONTACT CHAMBERxe2x80x9d, disclosing a water purification system that is effective to oxidize organic contaminants and to destroy most of the bacteria, viruses, and other microbes in such water stream.
Recently, after the events of Sep. 11, 2001, the possibility of terrorist attacks on the U.S. municipal water supplies or water distribution systems has attracted great public attention. By introducing chemical warfare agents (CWA), biological warfare agents (BWA), or radiological contaminants (RC) into such water sources, terrorists can inflict catastrophic injuries and losses of life within a short period of time.
Another concern relating to the viability of water sources is the possibility of pollution of water from industrial accidents and natural events such as tornados, hurricanes, earthquakes, and other severe weather and geologic events that may damage industrial facilities and distribution infrastructure, and result in pollution of water intended for human or animal use, or for agricultural and industrial operations. Such pollution may take many forms, and may likewise involve chemical contamination, biological contamination, and/or radiological contamination.
There is a continuing need for robust water purification systems for treatment of water that is or may be contaminated with chemical, biological and/or radiological contaminants.
Since contamination or threats of contamination of water are frequently of a highly local character, there is a correlative need for a fixed or portable water purification system that can be rapidly and easily deployed at a location of actual or potential contamination, particularly a system of such type that can effectively remove CWA, BWA, and/or RC contaminants (hereinafter xe2x80x9cCBRxe2x80x9d contaminants) from an actually or potentially contaminated water supply and produce treated water that is suitable for human consumption.
Since the risks attendant to terrorist attacks are particularly acute in relation to water supplies, there is also a compelling need for a water purification system having an anti-tamper character, to minimize the threat of willful disabling or destruction of such system.
Water purification systems of the foregoing type are needed that enable cleaning and servicing of components of the system without interruption of water treatment, and that are capable of evaluating the quality of treated water at a particular location in the treatment process and either diverting the water to drain or, optionally, recirculating and re-treating water that does not satisfy treated water quality standards.
The present invention in one aspect relates to a water purification system, preferably of a self-contained and portable character, for treatment of a water stream to remove chemical, biological, and/or radiological contaminants therefrom, comprising:
(a) an ozonation unit for ozone treatment of the water stream, comprising:
(i) an ozone contact chamber arranged to receive such water stream, mix such water stream with ozone, and discharge an ozonated water stream therefrom; and
(ii) an ozone supply arranged for variable output of ozone and coupled in ozone-supplying relationship to such ozone contact chamber;
(b) an ozone destruction unit downstream of such ozone contact chamber, for removing residual ozone from the ozonated water stream and converting such ozonated water stream into an oxygen-rich and ozone-depleted water stream; and
(c) at least one activated carbon adsorbent unit arranged to receive the oxygen-rich and ozone-depleted water stream from the ozone destruction unit, contact such water stream with activated carbon adsorbent, and discharge a treated water stream.
The present invention in another aspect relates to a method for treating a water stream to remove chemical, biological, and/or radiological contaminants, comprising the steps of:
(a) providing an ozonation unit comprising (i) an ozone contact chamber arranged to receive the water stream, mix such water stream with ozone, and discharge an ozonated water stream therefrom; and (ii) an ozone supply arranged for variable output of ozone and coupled in ozone-supplying relationship to the ozone contact chamber;
(b) flowing such water stream into the ozone contact chamber, mixing such water stream with ozone therein, and discharging the ozonated water stream therefrom;
(c) subsequently, passing the ozonated water stream through an ozone destruction unit to remove residual ozone contained therein and to convert such ozonated water stream into an oxygen-rich and ozone-depleted water stream;
(d) subsequently, passing the oxygen-rich and ozone-depleted water stream through at least one activated carbon adsorbent unit to contact such water stream with activated carbon adsorbent; and
(e) discharging a treated water stream.
The present invention in a further aspect relates to a self-contained, portable water purification system, comprising:
(a) an ozonation unit for ozone treatment of the water stream, comprising:
(i) an ozone contact chamber arranged to receive such water stream, mix such water stream with ozone, and discharge a ozonated water stream therefrom; and
(ii) an ozone supply arranged for variable output of ozone and coupled in ozone-supplying relationship to the ozone contact chamber;
(b) an ozone destruction unit downstream of such ozone contact chamber, for removing residual ozone from the ozonated water stream and converting the ozonated water stream into an oxygen-rich and ozone-depleted water stream, wherein the ozone destruction unit comprises at least one broad-spectrum radiation source for providing UV radiation having wavelength ranging from about 170 nm to about 300 nm; and
(c) a monitoring unit arranged to continuously monitor oxidation-reduction potential of the oxygen-rich and ozone-depleted water stream and to correlatively actuate the ozone supply to produce an output of ozone for maintaining the oxidation-reduction potential of such water stream at a predetermined level.
The present invention in a still further aspect relates to a method for purifying a water stream, comprising the steps of:
(a) providing an ozonation unit comprising (i) an ozone contact chamber arranged to receive the water stream, mix the water stream with ozone, and discharge an ozonated water stream therefrom; and (ii) an ozone supply arranged for variable output of ozone and coupled in ozone-supplying relationship to the ozone contact chamber;
(b) flowing such water stream into the ozone contact chamber, mixing said water stream with ozone therein, and discharging an ozonated water stream therefrom;
(c) subsequently, passing the ozonated water stream through an ozone destruction unit, so as to remove residual ozone contained therein and to convert such ozonated water stream into an oxygen-rich and ozone-depleted water stream, wherein the ozone destruction unit comprises at least one broad-spectrum radiation source for providing UV radiation having wavelength ranging from about 170 nm to about 300 nm; and
(d) discharging the treated water stream.
The present invention in a still further aspect relates to a system for treatment of water to remove chemical, biological, and/or radiological contaminants therefrom, such system comprising a unitary sealed housing arranged for connection to an external water source and having an anti-tamper character, wherein the unitary sealed housing has disposed therein one or more water treatment units arranged to treat water from the external water source to produce a treated water stream depleted of chemical, biological, and/or radiological contaminants, and wherein such unitary sealed housing comprises an outlet for discharging said treated water stream therefrom.
Additional aspects, features and embodiments of the invention will be more fully apparent from the ensuing disclosure and appended claims.